Thanks to contestants who have left the show, however, we do know more about how the contestants stay in shape throughout filming — and no, there's not a super secret "Bachelor" personal trainer living in the bowels of the "Bachelor" mansion.

They made do with what they had at the mansion.

ABC/Rick Rowell

The infamous "Bachelor" mansion doesn't come with a gym, so according to some contestants, they'd make do by running around the house or up hills. "Bachelor" 14 contestant Ashleigh Hunt said to Th e Ashley's Reality Roundup: "One day I ran laps around the outside of the house."

"There's no workout room here, but there's a hill in the back that girls would run up to exercise," Molly Mesnick, "Bachelor" season 13's runner-up and eventual winner, told The Ashley's Reality Round Up.

The contestants are also given gift bags when they arrive, according to the New York Post, which include yoga mats, and it's not uncommon to see some of the women or men do yoga, pilates, or body weight exercises in their free time.

And then there's Chad Johnson, one of the most famous villains on "The Bachelorette." A whole segment of the show was dedicated to him filling up his suitcase and strapping it to his waist before doing sets of pull ups.

"At the 'Bachelor' mansion, we had no weights — nothing at all," Johnson told BodyBuilding.com. "All I knew is it was back day, I had a weight belt, and the only thing that came to mind to be used as weight was my 60-pound luggage with a handle that would easily attach to my belt."

Now that's making use of what you have.

There's so much down time that most contestants say it's easy to find time to work out.

"Bachelorette" 10 contestant Brian Osborne agrees, and told Penn Live, "We worked out a ton. We tried to pass the time as best as possible with the limited resources we had."

When they were traveling, they got gym time — but not enough.

ABC

While the "Bachelor" mansion may not have a gym, the hotels where the contestants stayed definitely did. Of course, these small hotel gyms can't handle a huge group of women, so instead they got to work out in chunks.

"My workout time was cut in half," Courtney Robertson, "Bachelor" season 16 winner, told Yahoo Health, "so I would push myself more in the 30 minutes of time I had. Sometimes I would get more if someone else didn't schedule their 'yard time.' And I would try to squeeze in stretches and Pilates throughout the days."

The producers would find a time to bring the women down throughout the day without bringing attention to them and would limit them to 30 minutes.

"They take you down to the gym, usually alone," Robertson told Allure. "Only a couple times did I work out with the other girls. You get 30 minutes, which is pretty short. I would usually do the elliptical or run on the treadmill and then do crunches. If I had my own hotel room, I would do crunches and push-ups on my own."

"I gained weight through the process. There's a lot of food and alcohol at your disposal, which is hard," Robertson told Allure. "I usually tried to start drinking later in the night and watch myself. It can be stressful though. I remember overdoing it one night and waking up with an empty bag of Doritos in my bed."

"I watched everything I ate and counted calories," "Bachelorette" contestant Johnson said. "I remained in a caloric deficit at all times while on both shows. With all the food and drinks they put out, it would be easy to quickly make a noticeably negative difference in my appearance by gaining body fat."

But some contestants still think producers were wary of the contestants gaining weight and tried to limit them.

But they do make an effort to be inclusive with different dietary restrictions — and, of course, cravings.

"I'm vegetarian, Catherine's vegan, Kacie B's gluten-free. You cook for yourself, but at rose ceremonies they lay out a whole catered spread," Levans went on. "There was also a lot of candy. I recall eating so so so many M&Ms. There is, of course, no shortage of every single kind of alcohol you could imagine (in the house and in the limos) but it's a self-serve situation and you choose whether or not to partake. Clearly some partake in more than their fair share."